Adding New user to Role using the CreateUserWizard control

I am using the CreateUserWizard controls, but I want to modify the template to include a drop down which will be populated with the Roles created with the Web Admin Tool. These Roles are simple, like Admin, Usersmanagers, etc. I currently have a dropdown control outside the template and on code-behind I add this logic:

if (drprole.SelectedItem.Text == "Choose Role")
{Server.Transfer("~/CreateAccount.aspx"); }
else{// Adds the " ...